Obsterics US

• Confirming twins or multiples. Especially if you’ve had fertility treatments, this might be something you want to confirm ASAP (as soon as possible).
  
  
• Confirming fetal heartbeat. If you’ve had any concerning symptoms, like spotting or vaginal bleeding, your doctor will want to know if you’re experiencing a miscarriage or what the cause of any unexplained bleeding could be.
  
  
• Ruling out an ectopic pregnancy. When an embryo implants outside the uterus, you’ll often have pregnancy symptoms and a positive pregnancy test, even though the embryo isn’t viable. An ectopic pregnancy is a life threatening condition if it’s not treated, so it’s important to diagnose it.
  
  
• Checking your reproductive anatomy. Issues with your uterus, cervix, ovaries, or fallopian tubes can cause complications during pregnancy. So, if your doctor suspects you might have a problem — like uterine fibroids, for example — they may want to have that info right away.
  
  
• the embryo is simply too tiny for clear images to be detected. You may see the general shape of your baby or be able to tell something is there, but it’s also normal to not see anything that looks very much like a baby at all.
  
  
• One thing you will often see in a healthy pregnancy is your baby’s heartbeat. It could be going as fast as 110 beats per minute or more! If your baby is in a visible position on the ultrasound, you’ll probably see a little blinking or pulsing on the screen (and you should be able to hear it briefly, too).
  
  

• Gestational sac. This is one of the earliest visible signs of a pregnancy, and it refers to the fluid-filled space surrounding the embryo. It’s usually formed by 5 weeks of gestation, and it can accurately confirm an intrauterine pregnancy the vast majority of the time it’s seen on an ultrasound. It will look like a clear, dark circular or oblong shape, sharply contrasted with the whitish, opaque appearance of the inside of your uterus.
  
  
• Yolk sac. Even before you can see an embryo inside the gestational sac, you should spot the yolk sac. It’s the first thing to develop inside the gestational sac, and it provides your baby with nutrients and oxygen until the placenta develops. It’ll look like a small white ring or bubble inside the sac.
  
  
• Fetal pole. This is the first indication that your baby is forming inside the gestational sac. It will look like a thick, whitish shape attached to the yolk sac. Depending on how far along you are, it may be curved or oblong. It can usually be detected by 6 weeks of gestation on a transvaginal ultrasound. This is where you would see the baby’s heartbeat.
  
  

• What measurements will be taken (and why)
  

  Aside from detecting a heartbeat, the point of a 7-week ultrasound is to take measurements of these fetal developments so your doctor has a better idea of where you are in your pregnancy.
  That’s why this is often called a dating ultrasound: The measurements are a good indicator of gestational age.
  The technician will measure the size of your gestational sac and also take a crown-to-rump measurement of the embryo, if it’s visible. At 7 weeks, your baby should be about 5 to 9 millimeters (mm) in size and the gestational sac will be about 18 to 24 mm.
  At this point, fetal development is on a fast track and making large leaps in size from one week to the next.
  A gestational sac measuring well below 18 mm will probably reduce your gestational age — that is, your doctor might tell you you’re only 5 or 6 weeks pregnant, not 7. The opposite is true for a sac that measures much larger than 24 mm.
  Keep in mind that ultrasounds aren’t a perfect diagnostic tool, and things like the position of your baby can affect the accuracy of the measurements — or whether your technician is able to take them at all.
  If the results are inconclusive, your doctor may ask you to schedule another ultrasound in 1 or 2 weeks to try again.
  
  

Are twins visible this early?

What happens during the ultrasound at 8 weeks?

• Using a transvaginal approach the fetal heart beat nay be seen flickering before the fetal pole is even identified or measurable.
  
  
• It will be seen alongside the yolk sac.
  
  
• It may be below 100 beats per minute but this will increase to between 120- 180 beats per minute by 7 weeks.
  
  
• In the early scans at 5-6 weeks just visualising a heart beating is the important thing. Failure to identify fetal cardiac activity in a fetus whose overall length is greater than 4 mm is an ominous sign.